1. Field of the Invention
The present invention generally relates to a powdered metal process, and more particularly relates to an improved tool for use in a powdered metal compaction process having unique geometries and assembly methodologies.
2. Description of Related Art
The powdered metal process is well known in the art. The powdered metal process generally compacts a blend of dry, powdered materials such as but not limited to metal powders, graphite, lubricants, and other materials, etc., into a rigid compact or presintered form. This rigid compact is then sintered at a temperature sufficient to bond together the individual metallic particles to provide a net or near net shaped part. These sintered parts, depending on the desired materials properties and/or part requirements, may have additional manufacturing operations subsequently performed on them in a manufacturing environment. The powdered metal process also includes a plurality of other equipment used to create a sintered powdered metal part. This includes apparatus and methodology for transferring material and products via hoppers and discharge apparatus to the tooling and other machining is necessary to make the sintered powdered metal part. Many of these apparatuses that handle the transferred material are capable of transferring powder, dust, grains, pellets, tablets, capsules, particulate matter and the like to the appropriate location in the sintered powdered metal process.
Many types of tooling are required for the powdered metal process to ensure correct formation of the sintered metal parts. These tooling members must approximate the desired part geometry even those capable of having multi-level shapes and geometries. These tooling members generally include a die, a core rod and top and bottom punches. This tooling is generally the most limiting factor in achieving specific part geometries due to the complexity and/or the ability to provide sufficient strength and rigidity to such tooling to survive the compaction process and the high forces under which such compaction must occur. Many of these prior art part geometries consist of a cross section profile that do not have shapes that extend from center points of the part being made and thus any such continuously expanding path outward from a center area will offer unique challenges to powdered metal tooling and assembly of such tooling. Depending on the type of apparatus being made and the geometry of the rigid compact or form a core rod may or may not be required within the tooling for the powdered metal process. However, it should also be noted that multiple core rods and/or multiple top or bottom punches may also be utilized in the powdered metal process. During a compaction cycle compressive, tensile and rupture forces act differently on the individual tool members. It is well known in the art that each member must have adequate strength and rigidity to withstand these forces or cause shut down of the line and/or manufacture of parts that are not precisely built to specific dimensions. Therefore, tooling must be designed, configured and assembled as a package to achieve the desired compact or formed geometry as well survive the rigors of the compaction process in the powdered metal process.
Compaction is one of the essential elements in the powdered metal process. The compaction process generally includes the following cycle. First there is a filling cycle where a blend of powdered material is placed into a cavity created via a specific tooling member. Next, a compacting step is done where the material particles are compressed together as tightly as possible. Next, is an ejecting step where the compact or form is pushed from the cavity. Many process parameters such as time, force, tooling positions and tool deflections are monitored, controlled and changed during each cycle via the use of a compaction press. The compaction press generally has tooling aligned on a similar axis to create such compacts or forms.
Therefore, many problems have occurred in the prior art powdered metal process with complex geometries that tend to extend from the center or near the center of the compact in outward or other various unique geometries. The creation of a die core rod and top and bottom punches to achieve such unique shapes, while the punches still have the requisite rigidity and strength has not easily been achieved. Many prior art powdered metal processes are just not capable of creating unique specific geometries other than those of basic shapes. Therefore, there is a need in the art for powdered metal tooling that is capable of unique powdered metal geometries that have unique non-traditional design features that have specific design characteristics such that metal parts can be produced via a powdered metal process. The use of such unique tooling in a powdered metal process will reduce the overall cost of the component via lighter components for the manufacturer, quicker manufacturing times and more precise control over exact dimensional requirements for a powdered metal part.